Switch



Aug. 4, 1931. F. MEUNIER ET AL 1,317,013

I SWITCH I Filed March 2, 1929 2 Sheets-Sheet 1 INVENTORS Leo/7 f. Mean/er A TTORNE Y.

C/arence J. Dresser Aug. 4, 1931. L. F. MEUNIER ET 'AL' SWITCH Filed March 2, 1929 2 Sheets-Sheet 2 F S e Mr H 3 0 Wed W A 5 W. mr m M F V. B 3 2 Z a ,-.-\H 0 C 9 Z a /K 9 y T 0/0 a Patented Aug. 4, 1931 inmrau STATES PATENT OFFICE LEON F. MEUNIER AND CLARENCE J. DRESSER, OF CLEVELAND, OHIO, ASSIGNORS TO CHICAGO PNEUMATIC TOOL COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY Application filed March 2,

This invention relates to contact apparatus for electrical machines and devices, particularly portable electrical machines and tools. More specifically it relates to switches of the reversing type.

Among the objects of the invention are to provide a totally inclosed safety switch of compact form, to compel opening of the line before the machine or tool can be reversed, to utilize a single control member for starting and stoppin aswell as for reversing, to keep the switc mechanism in a tight inclosure and in a clean condition, and in general to improve prior devices in the interest of convenience, strength, safety, efiiciency, and durability.

The present invention avoids the necessity of using two switches, one for stoppin and starting and the other for reversing. avoids complicated and delicate interlocking means between such switches for preventing reversal of the current while the main switch remains on. It provides a single control member or handle which is so arranged that it is quite impossible to reverse the connections so long as the line remains closed. The control member has movement in two distinct senses, one movement for the primary current control and the other for reversal. In the form of the invention herein shown,'one movement of the handle is rotative for opening and closing the line, while an axial movement is utilized for reversing the connections. The arrangement is such that axial movement is impossible until the handle is first placed in, or turned to, the off position. During axial movement the handle cannot be turned to the on position until it has reached a predetermined position in such movement. The permissive movement of the control handle is determined by any suitable means which may include a U-shaped groove or channel.

In order to illustrate the invention one concrete embodiment thereof'is shown in the accompanying drawings, in which:

Fig. 1 is aplan view of the assembled switch showing the top plate largely cut away;

t also SWITCH 1929. Serial No. 848,972.

Fig. 2 is a View similar to Fig. 1 showing the switch in its reversing position;

Fig. 3 is a right end elevational view of the switch shown in Figs. 1 and 2;

1 Fig. 1 is a sectional View substantially on the-line 4.4 of Fig. 1;

Fig. 5 is a View similar to Fig. 4 showing certain of the parts in different positions;

.Fig. 6 is a longitudinal sectional view through the terminal support as on line 6 6 of Fig. 1; and

Fig. 7 is a detailedv sectional view substantially on the line 77 of Fig. 2.

. The embodiment of. the invention chosen for the purpose of illustration comprises a totally enclosed switch device having top and bottom plates 8 and 9 respectively forming the casing, an attachment plate 10 (Fig. 3) being provided for securing the switch to the machine or tool which is to be controlled thereby. A single operating member or shaft 11 projects from the casing and is provided with a suitable operating handle 12. Shaft 11 is arranged for movement in two distinct senses, one axial and the other rotative. By preference the rotative movement is utilized for opening and closing the line while the axial movement provides for the reversal of the connections. The arrangement is such that reversal cannot take place so long as the current is on. Suitable means are provided for determining the permissive movement of shaft 11, such as a U- shaped channel or groove 11a in the shaft (Figs. 1 and 2) engaged by the inner end of a pin 13 (Figs. 1, 2, and 3). Pin 13 is supported in thecasing and may extend through a bushing 14. (Figs. 1 and 2-) in which shaft 11 is slidably and rotatably supported. Shaft 11 has a reduced axial extension 15 which may be integral with or fixedly secured to the shaft asby a pin connection. Extension 15 is slidably and rotatably received in a bushing 16 in line with bushing 14.

The power cable 17 is secured to the switch casing in any suitable manner and the leads thereof extend to a series of fixed connections or terminals 18, 19, and 20 (Figs. 1, 2, and 6) mounted in an insulated terminal block 21, suitably secured within the casing in parallelism with control shaft 11, 15. Between terminals 18 and 19, and 19 and 20, are disposed upright barrier plates 22 and there are also barrier blocks 23 at the ends of bore 21 through which screws 21 extend to hold the terminal assembly in place.

The movable contacts and 26, which selectively engage either terminals 18 and 19 or 19 and 20, are supported on the control shaft 11, For this purpose a carrier 27, which may be square in shape as shown in Fig. 7, is rotatably mounted on the reduced shaft extension 15. Insulating material 28 is placed over the carrier and then the contact supports are secured thereon as by a clamping plate 25a, the plate and the support together conforming in shape to the exterior configuration of carrier 27. Shaft 11 has at its inner end an enlargement 11b and carrier 27 is held in abut-ting relation with this enlargement by a collar 29 which is pinned to shaft extension 15. Thus contact carrier 27 is held in fixed posi tion on control shaft 11, 15 for axial movement with the same. Barrier washers 30, 31, and 32 are disposed as indicated outside of and between movable contacts and 26.

The mounting of contact carrier 27 for rotation on shaft extension 15 utilized to cause the movable contacts to engage and leave the terminals with a snap action. To eil'ect this, carrier 27 is provided with a lever arm 33 which may be bent, as indicated, or otherwise formed to overhang enlargement 11b of shaft 11. Through a perforation 33a, in lever 32-), a. plunger 34L extends which has a grooved end 34a held in engagement with a pin supported in spaced ears 110 on enlargement 11?) by a coil spring 36. Thus loose or resilient connection is established between carrier 27 and control shaft 11. lVhen shaft 11 is rotated by handle 12, pin is oscillated about shaft extension 15 as a center and as it moves into line with perforation 330. it forces plunger 3i outwardly, so that the latter extends beyond a stop plate 37 on the casing which holds contact carrier 27 against movement while shaft 11, 15 continues to turn. l hen pin passes out of line with perforation 33a, plunger 31 is withdrawn until it no longer engages stop plate 37,whereupon spring operates to throw ca 'rier lever arm 33 with a snap action to its other position, indicated in broken lines in Fig.

The operation of the switch is as follows :Vith the parts in the position shown in Figs. 1 and 3, the switch is on to operate the machine or tool to which it is con nected. If it is desired to reverse the machine, handle 12 must be moved in a counter clock 'ise direction (Fig. 3) to the dotted line position, whereupon movable contacts 25 and 26 snap out of engagement with terminals 8 and 9. These contacts are now above barriers 22 and stop pin 13 is in line with the base of the U-groove in control shaft 11. A pull upon handle 12 moves the control shaft 11, 15 axially to the reverse position shown in Fig. 2. The line is still broken, however, and it is necessary to move the handle in a clock wise direction to cause contacts 25 and 26 to snap into engagement with terminals 19 and 2-0, whereupon the machine is operated in a reverse direction.

From the above it will be apparent that the present invention provides a single control member both for opening and closing the line and for reversing the connections, that it is quite impossible to reverse the machine so long as the current remains on, and that it is equally impossible to turn the current on until the control shaft is atone of the limits of its axial movement so that the movable contacts are in position to engage the switch terminals. This type of switch may be safely used in gas laden or other explosive atmospheres since any sparking or arcing of the terminals when the line is broken is entirely confined within the switch casing, the only possible outlet being along control shaft 11 which provides such a long bearing that an are or flame, or even an explosion within the switch casing, is quenched before it can reach the exterior of the casing.

\Vhile the invention has been herein disclosed in what is now considered to be a preferred form, it is to be understood that it is not restricted to the exact details thereof but covers all changes, modifications, and adaptations within the scope of the appended claims.

\Ve claim as our invention:

1. An electrical switch comprising a casing, a control shaft supported therein for limited axial and rotative movement, fixed and movable contacts arranged to be engaged and disengaged by rotative movement of said shaft, said movable contacts being mounted on said shaft for limited relative movement, and means utilizing the mount ing of said movable contacts on said shaft for causing said movable contacts to move with a snap action.

2. An electrical switch comprising a casing, a control shaft supported therein for limited axial and rotative movement, fixed and movable contacts arranged to be engaged and disengaged by rotative movement of said shaft, said movable contacts being mounted on said shaft for limited relativc movement, and means including a stop on said casing for utilizing the mounting of said movable contacts on said shaft for causing said movable contacts to move with a snap action.

3. An electrical switch of the reversing type comprising a totally enclosed casing, a control shaft projecting therefrom and arranged for both rotative and axial movement, and means restricting said rotative movement to one or more predetermined positions of axial adjustment, fixed terminals within said casing, movable contacts mounted on said shaft for engagement with said terminals in said positions of axial adjustment, and means for causing said movable contacts to move relative to said shaft and to engage and leave said terminals with a snap action.

4. An electrical switch of the reversing type comprising a totally enclosed casing, a control shaft projecting therefrom and arranged for both rotative and axial movement, and means restricting said rotative movement to one or more predetermined positions of axial adjustment, a series of fixed terminals within said casing disposed in parallelism with said shaft, movable contacts on said shaft for engagement with certain of said terminals in said positions of axial adjustment of said shaft, and barriers extending transversely to the axis of said shaft disposed between said terminals.

5. An electrical switch of the reversing .type comprising a totally enclosed casing,

a control shaft projecting therefrom, means providing for movement of said shaft in an axial direction and for limited rotation at the limits only of said axial movement, and means utilizing the rotative movement of said shaft for opening and closing the line and utilizing the axial movement of said shaft for putting the connections in position for reversal, a series of fixed terminals within said casing disposed in parallelism with said shaft, movable contacts mounted 011 said shaft for axial movement therewith but arranged for relative rotative movement, and means utilizing the mounting of said movable contact for causing the same to engage and leave said terminals with a snap action.

6. In an electrical switch having a shaft arranged for axial and rotative movement, a contact carrier rotatably supported on said shaft, and resilient means forming a loose connection between said carrier and said shaft.

7. An electrical switch of the reversing type comprising a casing, a single control shaft projecting therefrom and arranged for both rotative and axial movement in said casing, a contact carrier mounted on said shaft in a fixed position for axial movement therewith, and spring plunger means interposed between said shaft and said carrier for establishing a loose connection between the same. V

8. An electrical switch of the reversing type comprising a casing, a single control shaft projecting therefrom and arranged for both rotative and axial movement in said casing, a contact carrier mounted on said shaft in a fixed position for'axial movement therewith, spring plunger means interposed between said shaft and said carrier for establishing a loose connection between the same, and means on said casing engaged by said plunger means to retard the rotative movement of said carrier relative to said shaft so as to cause said carrier to have a delayed snap action.

9. An electrical switch of the reversing type comprising a totally enclosed casing, a control shaft projecting therefrom and arranged for both rotative and axial movement, and pin and slot means for determining the movement of said shaft.

10. An electrical switch of the reversing type comprising a totally enclosed casing, a control shaft projecting therefrom and arranged for both rotative and axial movement, said shaft having a slot formed there- I in with axial and transverse parts, and means on said casing engaging said slot to determine the permissive movement of said shaft.

11. An electrical switch of the reversing type comprising a totally enclosed casing, a control shaft projecting therefrom and arranged for both rotative and axial movement, pin andslot means for determining the movement of said shaft, mechanism within said casing operated by said shaft for utilizing movement of the latter in one direction for closing and opening the line with a snap action and movement in the other direction for reversing the connections.

12. An electrical switch of the reversing type comprising a totally enclosed casing,

a control shaft projecting therefrom, co-

operating means on said casin and shaft limiting the movement of the latter to a restricted axial movement and to a partial rotation at the limits of said axial movement, a series of terminals in said casing in parallelism with said shaft, contacts for engaging said terminals, a carrier for said contacts arranged on said shaft for axial movement with the latter but capable of relative rotative movement, an actuating arm on said carrier, a spring plunger loosely mounted on said arm and having a slotted end, a pin on said shaft engaged by the slotted end of said plunger, and a stop projection on said casing in the path of movement of said plunger to cause a delayed rotative movement of said carrier to effect a snap action.

Signed by us at Cleveland, in the county of Cuyahoga and State of Ohio this 25 day of February, 1929.

LEON F. MEUNIER. CLARENCE J. DRESSER. 

